Process of uniting metals.



f No. 'j129,sw3.` PATENTED JUNB.Kzf, 19os.

y H. GOLDSGHMIDT. PROCESS 0F UNITING METALS.

APPLICATION FILBDDEO. 3; 1900.#

'2 SHEETS-spurl.

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PATENTED JUNE 2, 190s.

- H. GOLDSGHMIDT.

PRocBss OPUNITING METALS.

'APPLICATION I ILBD DEO.'3, 1900.

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No 11701131...y

uonms versi: co.. mumumo.. vim-nauw n c navegan Y. l' n UNITED STATESPatented June 2, 1903.

:PATENT OFFICE.

HANS GOLDSCHMIDT, OF ESSENfO'NA-TI-IE- RUH/R, GERMANY, ASSIGNOR TOCLARENCE B. SCHULTZ,"OF BERLIN, GERMANY.

PRooEss o F uNmNe METALS.

SPECIFICATION forming part of Letters Patent No. 729,573, dated June 21903. Application iiledDecemher 3, 1900.v Serial No. 38,583. (No model.)

To all whom t may concern,.-

Be it known that I, HANS GoLDsoHMIDT, a subject ofthe King of Prussia,German Emperor, and-a resident of Essen-on-the-Ruhr,

in the Province of the Rhine, German Empire, have invented a new a-ndImproved .Process of Welding Metals, of whichthe following is an exactspecification.

The present invention relates to a process for welding metal pieces,particularlyjiron or steel pieces, and forms in a manner a process forsoldering and at the same time for'welding metal pieces.

The process is based upon the knowledge that whereas under ordinarycircumstances molten iron cannot be cast upon iron'sur-z faces so as tostick at once fast the problem is solved when the metal is used in ahighlyheatedl state, in which it results from the oxidV by the use ofaluminium, as shown by my former United States Letters Patent,No. 578,868. The effect of the process can beexplained thus: that inconsequence of the highly-' heated iron the adjacent parts of the ironpieces to be joined with the metal added by casting Abecome quicklyheated to the welding or smelting temperature and adopt the capacity ofbecoming joined with the metal cast upon them.

The process can bevused for different purposes. It can serve forrepairing damaged or defective cast or rolled iron pieces, wherebylacking parts may be easily renewed or two parts which in an undesiredor defective man.-

ner are separated from each other can be again rejoined. The process mayalso ordi--A narily be used for joining two metalpieces by means of thehighly-heated metal cast upon them. In any case it is an essentialfeaturethat the metal added by casting, owing to its highly-heated statein which it re'sultsfromV the alumina-thermo process, is aptto form atthe same time a joining or compensating material (soldering, casting)and, o'n the other hand, a heatingmaterial, (welding.)

In order 'to make my invention more clear, I referto the accompanyingdrawings, in which similar letters denote similar parts, and in which-Figure 1 shows a perspective view of two rails to be welded, thewelding-surfaces being I level. Fig. 2 is a similar view of a modifiedform of welding; and Fig. 3 shows an elevation of two rails to bewelded, the weldingsurfiz-ces overlapping each other. Fig. 4 is a vertical section of a rail, showing the arrangement of the clamping devicefor pressing the rails to be welded together. Fig. 5 is a side view ofthev device shown in Fig. 4.

Fig. l relates to a welding of two rails in which vthe process iscarried out in such a manner that between the surfaces of both metalpieces to be welded highly-heated molten metal produced according to thealu mina'- therzn'o process is cast. The temperature of the added metalis so highV that the extremities of both pieces to be welded adopt atemperature at which they become soft, and thus pass into a state inwhich they are apt of being joined.- In order to accelerate theestablishmentof this state, the extremities of the metal pieces maypreviously be heated.

Tlie employment of the alumina-thermo Aprocess for the production of thehighlyheatediron has the advantage that the temperature of the metal tobe produced, its chemical purity, and composition can easily beascertained, which is not possible to such anl extent with other heatingprocesses, andl has the further advantage that a metal can be producedthe temperature of which is far beyond the melting-point of the ironwithout the risk of changing this iron with regard to its purity and theoxidation of the same.

The process is carried out in the following manner: v The two rails tobe joined are placed in. a certain distance to each other after thejoint-surfaces have been carefully cleaned or, if'possible, renderedrough or grooved, and the joint-surface has been surrounded by asuitable mold into which the highly-heated iron is cast.

In Fig. l, a and b illustrate the rails. `c is a suitable mold, and dthe joint.

The welding may also be accelerated by compressing the metal castbetween the two rails, which is obtained by means of a suitable clampingapparatus, the construction of which is shown in Figs. 4 and 5 of thedrawings. The apparatus consists of two clamp- IOO ing-jaws which areconnected by means ofa connecting-rod. The jaws consist of two pieces eand f, which are connected to each other by means of the screws g. Thepieces e and f are provided with grooves into which the rail tits, asmay be seen from Fig. 4. By screwing the nuts 7L of the screws g downthe rail is perfectly fixed between the pieces e and f. Near the joinedsurface of each of the rails a and b to be joined one of the clamps soformed is fixed. On both sides of the lower piecefslots t are provided,in which slots a bar 7c, provided with a fixed head Zon one side, andwith screw-threads m on the other side is situated. Upon the threads m anut n is provided, by t-he screwing down of which nut the clamping-jawsare brought nearer to one another, thereby pressing the joined surfacesof the rails a and b together.

The highly-heated iron used in this process is obtained in the followingmanner: A mixture of aluminium and oxid of iron, (the latter chemicallyas pure asy possible,) to which mixture sesquioxid of manganese, oXid ofchromium, or Wolfram-acid may be added, is brought to reaction by meansof ignitin g pellets. After the reaction is completed the contents ofthe crucible in which the reaction has been carried out consists of alayer of molten alumina vIioating on the top and underneath this layerhighly-heated m01- ten iron. Now at rst the molten alumina is removedand then the highly-heated iron is cast between the carefully-cleanedwelding-surfaces situated in a certain distance to each other. As soonas the metal is congealed it is put under a certain pressure by screwingthe nuts n down, so that the metal will gradually cool down undercompression. After the mold c has now been removed the joint may stillbe exposed toa finishing work.

It will be clear that the surfaces to be joined may have any convenientform and that the process can be used for joining any suitable metal.

The direction of the pressure exercised upon the pieces to be weldedafter the highlyheated metal being cast between the same dependsnaturally upon the form of the surface to be joined. It', for instance,there are angular surfaces to be welded, then the pressure must beexercised in a diagonal line or in the resultant of two lines beingnormal to the two angular welding-surfaces- In Fig. 2 a plate q isshown, having an angular cut into which a plate p is pressed. Thepressure must here be exercised in the direction of t-he resultant r(indicated by the arrow) after the highly-heated metal has been castbetween the welding-surfaces of the plates p and q. The mold is notshown in this figure.

In Fig. 3 another modification of welding is shown for the case of twooverlapping surfaces. B y welding two rails overlapping each other alarge joint-surface is created, so that the durability of the joint isincreased.

In the same manner described above defective cast, rolled, or weld ironpieces can be mended. For instance, there is a toothed wheel in which atooth is broken olf. In order to fix a new tooth on the respectiveplace, the mold having a free space corresponding to the shape of thetooth is mounted upon the damaged part by means of molding-sand or thelike. Then highly-heated iron, preferably corresponding in its chemicalcomposition to the material of the piece to be welded,

.is cast into the mold. The metal becomes welded to the wheel, owing tothe highly-heated state, in such a manner that the joint is but littleor not at all less strong than the piece to be welded. 'lhe formation ofa tight joint of the metal added by casting with the pieces to be weldedbesides bya mechanical compression can still be accelerated by heatingthe ground material before casting the highly-heated material upon thesame.

This heating can be obtained by casting upon the ground material thealumina resulting from the reaction of aluminium and oxid of iron andalso advantageously by a small coalespecially charcoal-blast-ame. Forinstance, after having adjusted the rails a certain quantity of charcoalmay be placed around the joint and then heated under adownwardly-directed draft, thereby rendering the rail extremitiesred-hot. Thereafter it is only necessary to remove the charcoal and toclean the welding-surfaces by blowing ofi.v the ashes, so that the railsare ready to become welded by casting the metal between thewelding-surfaces.

Having thus fully described the nature of my said invention, what Idesire to secure by Letters Patent of the United States is 1. A processfor adding metal pieces or tilling out hollow spaces by casting,consisting in igniting a mixture ot' a metal compound with aluminium,removing the alumina resulting from the reaction taking place and thencasting the highly-heated metal into the spaces, substantially asdescribed and for the purpose set forth.

2. A process for welding metal pieces, consisting in cleaning thejoint-surfaces, placing the pieces in a certain distance to each other,surrounding the ends to be joined witha mold, igniting a mixture of ametal compound and aluminium, removing the alumina resulting from thereaction taking place and casting the highly-heated metal between thejointsurfaces, substantially as described and for the purpose set forth.

3. A process for welding metal pieces, consisting in cleaning thejoint-surfaces, placing the pieces in a certain distance to each other,surrounding the ends to be joined with a mold, igniting a mixture of ametal compound and aluminium, removing the alumina resulting from thereaction taking place, casting the highly-heated metal between thejoint-surfaces and pressing the pieces together as soon as the metalcast between the same is congealed, substantially as described and forthe purpose set forth.

4. A process for Welding metal pieces, con- IOO IIO

sisting in cleaning the joint-surfaces, placing the pieces inY a certaindistance to each other, surrounding the ends to be joined with a mold,heating these ends, igniting the mixture of a metal compound andaluminium, removing the alumina resulting from the reaction takingplace, casting the highly-heatedmetal l between the joint-surfacesandpressing the pieces together as soon as the metal cast be-

